The present invention relates to an electrical connector for an electronic memory smart card with large storage capacity, such as an SD (Secure Digital) card marketed by SANDISK. All the features and performance characteristics of the SD card are defined in the documents issued by the SDCA (SD Card Association), the address of which is 53 Muckelemi St., P.O. Box 189, San Juan Bautista, Calif. 95045-0189 USA.
This SD card belongs to the family of memory cards already containing MMC (Multimedia Card) cards, these two types of card being marketed by SANDISK. The overall dimensions of MMC and SD cards are identical with the notable exception of the thickness of the SD card which is greater, this increase corresponding to the increase in memory capacity of such a card. The invention also relates to a connector for connecting another card with large storage capacity known as an MSD (Memory Stick Duo) card marketed by SONY. All of the features and performance characteristics of the MSD card are defined in the document published by the SONY Corporation and entitled “Memory Stick Standard—Memory Stick Duo Format Specification ver. 1.0—August 2001”.
In general, a card is placed in a position of full insertion, in which the card is electrically connected, and the card extracted by the user after use using ejection means built into a connector. The connector should be compact, economical, and contain a low number of parts. The total length of the “card+connector” assembly needs to be reduced as far as possible, because it may dictate the size of small equipment such as a cell phone.
According to a first known design used for example in performing banking transactions, the apparatus uses motorized means to eject the card to a position such that the card can be gripped by the user. In another design, the fully inserted card protrudes by more than a centimeter from the connector to allow the user to grasp the card rear portion and pull it horizontally out of the connector. However, when the card is small in size, particularly in the longitudinal direction, it is difficult to have the card projects from the receiving device by just a few millimeters from the connector so the card can be grasped.
Applicant previously has proposed a design of electrical connector able with equal ease to take either SD cards or MMC cards, which is particularly compact but also does not incorporate means for ejecting the card from the connector. When the connector, on the printed circuit board that bears it, is surrounded by components or by other elements belonging to the electronic equipment equipped with the connector, it is impossible for the card to be inserted or extracted in the horizontal longitudinal direction, manually or automatically using ejection means built into the connector.
There has previously been described in WO-A-98/13784 (The Whitaker Corporation) a connector for a SIM (Subscriber Identification Module) or MICROSIM type card of rectangular overall shape and comprising, in a central region of its lower main face, conducting pads which engage contact ends of elastically deformable conducting blades on the horizontal bottom of a card housing. Such connector has an element for manually locking the card, which element slides between a forward position allowing the card to be put in place and a rear position in which it holds the card in the horizontal contact position in which an upper part of the moving locking element extends over the upper face of the card.
Such a design allows the card to be inserted generally in a vertical direction by bringing the card “over” the connector. However, handling is complicated and the proposed design is specific to a MICROSIM card. In addition, this design entails a translational movement in the lengthwise direction of the card, and a thickness of wall of insulating material behind the transverse rear edge of the card. These two requirements entail a corresponding increase in the lengthwise size of the “card+connector” assembly. In order to achieve partial ejection of the card by tilting thereof, this design additionally envisages a molded plastic elastic blade extending over the card and increasing the total thickness or height of the connector.
It is desirable for the card to be able to be inserted and extracted within a small volume, corresponding to a volume bounded lengthwise by the front end edge of the insulating body of the connector and by the rear transverse edge of the card when the card is in a horizontal contact position in the connector. In this position a wall or components faces and substantially contacts the rear edge of the card. It is desirable that handling of the card can be performed without any longitudinal movement of the card in the horizontal plane.